Tŷ Du Observatory

After installing Registax 5 beta I thought I’d have a go at reprocessing the moon images I took the first time I used the Canon 300D. I had 8 frames that could be stacked but I wasn’t able to do this in Registax 4 and finally published a processed single frame.

I think the 8 frame stack is an improvement but I may revisit and tweak the image as I learn more about the wavelet values and how to tease the most detail from the image.  After processing in Registax I finished the image, curves and levels, using the Gimp.

Everyone seems to be taking shots at Lulin at the moment but I haven’t had a clear night for weeks.  Sunday was my first opportunity to take a look at the green comet and  even though Starry Night showed it as being behind my house until after 11pm, it actually appeared in the gap between my house and the neighbours so I was able to image a little earlier than expected.

As the comet is moving quickly against the background I kept exposures to 20 seconds, which in hindsight was not long enough. I’ve spent hours trying to extract as much detail as I can from the 49 frames I took, but my best image is a stack of only 24.

Taken with the usual setup, 1200mm fl 254mm newtonian scope on EQ6 mount. Starry Night, EQMOD, Canon 300D (unmodded). Guided with 70mm cheapo scope using QHY5 guide camera.

As a footnote, I must try and get the Atik 16ic configured as my guider.  The QHY5 is so unreliable, both Guidemaster and PHD crash when using it. I have found that if I leave PHD with the error message on the screen it continues to guide regardless

In the same session I also managed to get a few 3 minute guided frames of M51.  I’ve not been able to get more than 1 minute subs previously, but the guider worked for most of the session, so I’ve been able to stack 20 frames to make this image:

It’s nice to have a colour camera to get these galaxy shots but I think I need to go longer than 3 minutes! Coma is very obvious even in this heavily cropped image – I think I may need to invest in a coma corrector next.

I’ve had a good start to 2009. Not only have I got the autoguiding working with a new guide camera (QHY-5) but I managed to pick up a bargain from ebay last weekend.  I purchased a Canon EOS 300D digital SLR camera for just £80 due to a broken pin in the memory card slot.  I’d put in a work-around within 20minutes and ordered an EOS to M42 adpater straight away. The adapter arrived yesterday, but what appeared to be a clear sky turned into fog and I had no chance to test things out.

I spent the time indoors making a long exposure cable for the Canon using some diagrams I’d found online.  I don’t need auto focus just “bulb” control so the circuit is a simple transister switch running from the parallel port.

Today has been overcast all day so I was surprised to see Venus through the kitchen window when I went to cook dinner. A closer look and my hopes were dashed, it was foggy again, but not as bad as last night. At the front of the house I could see the full moon with a halo around it as it shone through the fog. But I knew it wasn’t worth setting up, everything was against me.

I took some time to add the new camera details to Starry Night so that I could compare the field of view with that of the Atik 16ic – WOW what a difference. Using the software I panned from galaxy to nebula to cluster to …. the Moon, and found the whole moon fitted in the field of view – and there was a full moon at the moment. Well that changed my mind and I gathered my equipment and started setting up with a view to using the full moon to help me focus the Canon camera.

My first shots were not bad but I moved the focus in then out, then back in until I thought it was close.  I then used the canon remote software to take a series of images with a view to stacking them – but I couldn’t get the stacking to work, I may revisit that.

So here is my “first light” with the Canon EOS 300D. It’s a single frame taken with the camera set to portrait (I’m not familiar with the manual settings yet) and using a 10″ Newtonian Skywatcher on an EQ6Pro mount. EQMod was used to find then track the moon in “lunar” mode.

Image processed using the GIMP on Ubuntu Linux.

Image details: ISO 100, 1/500s.